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4.4 Translating and Setting Page Table Entries

This set of functions and macros deal with the mapping of addresses and pages to PTE's and the setting the individual entries.

mk_pte takes a physical page and protection bits and combines them together to form the pte_t that needs to be inserted into the page table. A similar macro mk_pte_phys exists which treats the address as a physical address.

pte_page returns the struct page which corresponds to the PTE entry. pmd_page returns the struct page containing the set of PTE's.

set_pte takes a pte_t such as that returned by mk_pte and places it within the processes page tables. pte_clear is the reverse operation. An additional function is provided called ptep_get_and_clear which clears an entry from the process page table and returns the pte_t. This is important when some modification needs to be made to either the PTE protection or the struct page itself.


next up previous contents index
Next: 4.5 Allocating and Freeing Up: 4. Page Table Management Previous: 4.3 Using Page Table   Contents   Index
Mel 2003-01-14